Coconut flour

Coconut flour is notable for nickel, salicylate, FODMAPs, histamine, sucrose, sorbitol and fructose. Clear on tyramine, lactose, oligosaccharides, oxalates and gluten.

Yes — coconut flour is high in nickel. Coconut flour is dried, defatted coconut ground fine, so the nickel of the flesh arrives concentrated - and it is used in large proportions in gluten-free baking. The flesh's nickel is the measured part - the flour concentrates it by drying.

Coconut flour contains moderate levels of salicylate. Coconut is milder in salicylate than tree nuts, but flour is a concentrated format: a cake uses far more coconut than anyone eats as fruit.

Coconut flour contains moderate levels of FODMAPs. Coconut flour carries both sorbitol and fructans, and it is used in large proportions in gluten-free baking - a cup of it where wheat flour would have gone. The quantity is what puts it here, not the concentration.

Coconut flour contains only low levels of histamine. Coconut flour is a dry milled product, and dryness is what keeps it low - amine-producing bacteria need moisture. It is what the flour becomes that matters: a long-fermented dough is a different question from the flour it started as. Amounts vary by brand and recipe, so always check the label of the exact product.